SU707912A1 - Method of preparing alkylaromatic hydrocarbons peroxides - Google Patents

Description

one

The present invention relates to an improved method for producing alkyl aromatic hydrocarbon hydroperoxides: which are used as initiators for the polymerization of unsaturated hydrocarbons and as a starting material for the synthesis of phenols, epoxy compounds, alkyl aromatic alcohols, and aromatic peroxides.

A known method for producing alkyl aromatic hydrocarbon hydroperoxides by oxidizing the corresponding hydrocarbons with oxygen-containing gas in the presence of alkali and alkaline earth metal hydroxides, carbonates and bicarbonates is used to neutralize acidic products and increase the conversion of the starting hydrocarbons 1.

The disadvantage of this method of oxidizing alkyl aromatic hydrocarbons in the presence of various additives is the low selectivity of hydroperoxide formation, as a rule, not exceeding 90-92%.

Thus, in this method hydroperoxides are obtained by oxidation of alkyl aromatic hydrocarbons in the presence of

two alkaline stabilizing substances - carbonates of alkali or alkaline earth metals and co. pei weak organic acids, for example, calcium stearate H.TIH calcium with an output of the oxidized product: hydroperoxide isopropyl hexazole 91, diisopropyl benzene hydroperoxide 76-81%. The rate of accumulation of hydropero-acid isopropylbenzene at 80 ° C is 0.87% / h.

The closest solution to the stated technical problem is the method of pulling hydroperoxides.

5 alkylaromatic hydrocarbons by oxidation of the corresponding hydrocarbons in the presence of catalysts of metal salts of variable valence of catalysts and monobasic fatty acids, for example, copper or silver formates or acetates 12.

The process is carried out by oxidizing alkylaromatic hydrocarbons with oxygen or oxygen-containing

5 gas at a temperature of 70-125 C,

The disadvantage of this method is the low consumption of the target product - isopropyl benzene hydroperoxide.

5-90%, mono- and dihydroperoxides, nieopropyl benzene - about 75%.

The purpose of the present invention is to increase the yield of the target product.

According to the invention, the goal is achieved by the fact that alkyl aromatic hydrocarbon hydrocarbon oxides are obtained by liquid-phase oxidation of the corresponding hydrocarbons with oxygen or oxygen-containing gas at a temperature of 70-125 ° C in the presence of a catalyst. The catalyst used is a salt of a variable valence metal and monobasic fatty acid.

A distinctive feature of this method is the process in the presence of borax-phosphate or phosphate, or phosphate-alkali; buffer solutions, taken in an amount of 0.1-10.0% by weight of hydrocarbon at a pH of 6-9. Buffer solutions are prepared by mixing 2 solutions in a certain ratio, depending on the required pH.

A phosphate-alkaline buffer solution that maintains a pH of 6.0 is prepared by mixing 50 ml of a 0.1N solution, 5.7 ml of a 0.1N solution of NaOH and 44.3 ml of water, a phosphate-alkaline buffer solution that maintains pH of 8 , 0, prepared by mixing 50 ml of a 0.1N solution of KR, 46.8 ml of a 0, 1N solution of NaOH and 3.2 ml of water; phosphate buffer solution, which maintains pH of 8.0, is prepared by mixing 94.5 ml of 1 / 15M solution of NagHPO and 5.5 ml of 1 / 15M solution, - borax-phosphate buffer solution, ensuring maintenance of pH 9, Oh, ready t by mixing 83 ml of 0.05 M solution, 10 and 17 ml of O, 1N solution.

Available and low-cost components, such as caustic soda, borax, and potassium acid phosphates, are used to prepare buffer solutions.

The buffer solution is added to the initial hydrocarbon, heated to a predetermined temperature and containing the catalyst,

As a catalyst, stearates, naphthenates, benzoates, resins of copper, manganese, nickel, can be used.

The process is carried out at atmospheric pressure. In the case of carrying out the process at temperatures above 100 ° C, it is necessary to compensate for the entrainment of water from the reaction zone or to carry out the process at elevated pressure.

When the content of oxidate is 20.0-25.8% of hydroperoxide, the yield of the target product is 92.9-96, l% t Thus, the proposed casting allows to significantly increase the yield of alkyl aromatic hydroreoxides, which is achieved by carrying out a catalytic oxidation process of alkyl aromatic hydrocarbons , in the presence of bora-phosphate phosphate or phosphate-alkali buffer solutions.

Example 1, 100 ml of isopropylbenzene is oxidized with air oxygen in a bubble-type reactor at 100 ° C in the presence of 0.0166 wt.% Copper stearate and 2 ml of phosphate-alkaline buffer solution (2.3% by weight of hydrocarbon), pH of the reaction mixture is 8 , 0, After 5 h of oxidation, a reaction mass containing 23.8% hydroperoxide, 0.1% acetophenone and 1.8% dimethylphenylcarbinol is obtained. The oxidation rate to hydroperoxide is .4.8% / h. The yield of hydroperoxide on the oxidized isopropylbenzene is 91.6%.

Example 2, under the conditions of Example 1, 100 ml of isopropylbenzene are oxidized in the presence of 0.0023 wt.% Copper stearate and 0.2 ml of phosphate-alkaline buffer solution (0.23% by weight of hydrocarbon), the pH of the reaction mixture is 6.0. After 6 hours of oxidation, a reaction mass containing 25.8% of hydroperoxide, 0.07% of acetophenone and 1.5% of dimethylphenylcarbinol is obtained. The oxidation rate of isopropylbenzene to hydroperoxide is 4.3% / h. The yield of isopropyl benzene hydroperoxide on the oxidized product is 93.7%.

Example 3. Under the conditions of example 1, 100 ml of isopropyl benzene in the presence of 0.0023 wt.% Copper stearate and 1.0 ml of phosphate-alkaline buffer solution (1.15% by weight of the hydrocarbon) are pH-oxidized with air. The pH of the reaction mixture is 6.0 . After 6 hours of oxidation, a reaction mass is obtained containing 25.5% isopropyl benzene hydroperoxide, 0.08% acetophenone and 1.7% dimethylphenylcarbinol. The rate of oxidation to hydroperoxide is 3, 35% / h. Hydroperoxide yield on oxidized isopropylbenzene - 92.9%.

Claims (1)

Example 4. 100 ml of m-diisopropylbenzene is oxidized by oxygen. air at 90s in the presence of 0.0116% by weight of copper stearate and 2 ml of phosphate buffer solution (2.3% by weight of hydrocarbon), pH of the reaction mixture is 8.0. After 12 hours of oxidation, a reaction mass is obtained containing 44.55% monohydroperoxide , 2.22% oxyhydroperoxide, 12.31% ligidroperekisi and 2.70% m-isopropylphenyldimethylcarbinol, the total content of hydroperoxides in units of monohydroperoxide is 67.74%. Hydrocarbon oxidation rate in hydroperoxide 5, b5% / h, Composition of oxidation products: monohydroperoxide - 72.1%, dihydro5-peroxide - 19.9%, by-products8, 0%, Yield of mono- and ligiproperoxide on oxidized diisopropyl benzene -9 Example 5 100 ml of m-diisopropylbenzene is oxidized by air at 90 ° C in the presence of 0.058% by weight of nickel stearate and 7 ml of borax-phosphate buffer solution (8.1% by weight of hydrocarbon), the pH of the reaction mixture is 9.0. After 12 hours of oxidation, a reaction mass containing 35.41 monohydroperoxides, 0.50% oxyhydroperoxide, and 5.24% dihydroperoxide is obtained. and 1.08% m-isopropylphenyldimethyl carbinol. The total content of hydroperoxides in units of monohydroperoxide is 44.5%. The oxidation rate of hydrogen to hydrogen in hydroperoxide is 3.7% / h. The output of mono - and dihydroperoxide on oxidized diisopropylbenzene 96, 0%. Example 6. 100 ml of p-diisopr pilbenzene is oxidized with atmospheric oxygen at 90 ° C in the presence of 0.058% by weight of nickel stearate and 8.65 ml of borax-phosphate buffer solution (10% by weight of hydrocarbon) at a pH of the reaction mass of 9.0. The rate of oxidation of hydrocarbon laziness in monohydroperoxide is 3.9% / h. The oxidation is carried out until the monohydroperoxide content in the oxidate is 20.1%. The yield of monohydroperoxide p-diisopropylbenzene is 96.1%. Example 7. 100 MP of p-diisopropylbenzene are oxidized with air acid in the presence of 0.086 ml of phosphate-alkaline buffer solution (0.1% by weight of hydrocarbon) under the conditions of example 1 for 4.5 hours until the monohydroperoxide content in the oxidate is 30.8% The yield of p-diisopropylbenzene monohydroperoxide is 92.3%. The method of obtaining hydroxperoxides of xylacytic hydrocarbons by liquid-phase oxidation of the corresponding hydrocarbons with oxygen or oxygen-containing gas at a temperature of 70-125 ° C in the presence of a catalyst — a variable-valence metal salt and a monobasic fatty acid, characterized in that the process is carried out in order to increase the yield of the desired product. the presence of borax-phosphate or phosphate or phosphate-alkaline buffer solutions, taken in an amount of 0.1-10.0% by weight of the hydrocarbon at a pH equal to 6-9. Sources of information taken into account in the examination 1. Patent-UK No. 758934, cl. C 2 C, pub. 1961. 2 o Patent of Great Britain No. 11,22732, cl., C 2 C, published. 1969 (prototype)